Background <p>Preoperative carbohydrate loading is a crucial component of ERAS protocols. However, its effectiveness has not previously been evaluated in neurosurgery. This systematic review and meta-analysis aimed to assess the postoperative effectiveness of preoperative carbohydrate loading in neurosurgery.</p> Methods <p>The EBSCOhost, PubMed, Scopus, Ovid LWW Total Access, Web of Science, and Cochrane Central Register of Controlled Trials databases were searched up to November 2024. Randomized and nonrandomized controlled trials involving patients aged 18 and above who underwent any type of elective neurosurgery and received any form of preoperative oral carbohydrate beverage were included. The primary outcomes were total and postoperative length of hospital stay (LOS). The secondary outcomes were 30-day readmission, total cost of hospitalization, ambulation on postoperative day (POD) 1, oral intake time, pain, postoperative nausea and vomiting (PONV), and complications. The methodological quality and risk of bias of the selected studies were assessed. Review Manager 5.4 software and Comprehensive Meta-Analysis v4 software were used for the statistical analyses.</p> Results <p>A total of nine studies involving 1,299 patients were included in the assessment of total hospital LOS, and six studies involving 761 patients were included in the examination of postoperative hospital LOS. The total hospital LOS (MD = -1.75 days, 95% CI: -2.78 to -0.73, <i>p</i> = 0.0008) and postoperative hospital LOS (MD = -3.40 days, 95% CI: -4.80 to -2.00, <i>p</i> &lt; 0.00001) were significantly shorter in the intervention group. In addition, the intervention group had a significantly higher rate of ambulation on POD 1 (OR = 12.84, 95% CI: 2.85–57.77, <i>p</i> = 0.0009), whereas the rates of pain (OR = 0.18, 95% CI: 0.13–0.26, <i>p</i> &lt; 0.00001) and PONV (OR = 0.37, 95% CI: 0.25–0.53, <i>p</i> &lt; 0.00001) decreased. The results regarding the total cost of hospitalization, oral intake time, and respiratory system complications should be interpreted with caution.</p> Conclusion <p>Preoperative carbohydrate loading is effective in improving postoperative patient outcomes during neurosurgery. It is recommended that institutions support preoperative carbohydrate loading by establishing guideline-based written protocols and integrating it with other evidence-based strategies to enhance surgical outcomes.</p> Trial registration <p>Registration number International prospective register of systematic reviews (PROSPERO): CRD42024577131.</p>